1. Field of the Invention
The present invention relates to a blade inspection apparatus and a blade inspection method for inspecting blades of an engine.
2. Description of the Related Art
Inspections of blades of jet engines or the like have been conventionally performed. An inspector performs a blade inspection, for example, by inserting an insertion section of a borescope, i.e., an endoscope, into an engine from an access port provided in the casing of the engine and by producing on a monitor a display of an endoscopic image of a blade in the engine.
An endoscopic apparatus has been proposed with which automation of the inspection process (labor saving) is performed so that the number of inspection process steps in inspection of blades of an engine is reduced, as disclosed in Japanese Patent Application Laid-Open Publication No. 2007-163723, and which is thus capable of reducing the complicatedness in an object inspection. Ordinarily, however, a blade inspection is performed with a borescope held by an inspector.
When a defective is found in a blade by inspection, a need may arise to produce an enlarged display of the defective portion and examine the defective portion in detail, depending on the size of the defect. Therefore, borescopes of various view angles are provided. An inspector first inspects a blade through a large area by using a borescope of a wide view angle and thereafter performs a detailed inspection by using a borescope of a narrow view angle and displaying an enlarged image of a defective portion on a monitor. An observation window through which light is received from the object is disposed in a distal end portion in the insertion section of the borescope.